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Gelneren [198K]

3 years ago

10

Rolf spent 15 hours last week practicing his saxophone. If 3/10 of the time was spent practicing warm up routines, how much time

did he spend practicing warm up routines

1 answer:

agasfer [191]3 years ago

4 0

Four point five (4.5)

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Lines a and b are parallel. Find the measure of each angle. Angle 8 is 113 degrees

pentagon [3]

Answer:

angles 1 4 and 5 are all equal to 113 and angles 2 3 6 and 7 equal 67

3 0

3 years ago

The figure shows a line graph and two shaded triangles to find the slope: (picture below)

just olya [345]

Answer:

the answer is d because it is

7 0

3 years ago

Read 2 more answers

Jerry goes to a theme park to ride the roller coasters. The theme park charges an entry fee in addition to a fee for each roller

ratelena [41]

You start with: (assuming x equals the cost to enter and y the cost of going on the rollercoasters.)
x+5y=35
x+11y=59. Multiply the top equation by -1, and subtract the equations, giving you -6y=-24, divide by -6 into both sides of the equation, to get y=4. Now replace y in one of the original equations (I recommend x+5y=35) and solve for x, giving you x=15

The cost for entering is 15 dollars, while each coaster is 4 dollars more. You could simplify this by changing y into x and making it slope-intercept form, to track your cost. y=4x+15, so it has a slope of 4, and a y-intercept of 15. This answer should give you a good grade on a test.

7 0

2 years ago

A box is to be wrapped in a shiny red decorative paper.The box is 9 inches long,5 inches wide,and 4 inches high.How much wrappin

Gnoma [55]

Answer:

Draw a figure!

There are 6 surfaces to add.

4 of them have area 9*5 and 2 have area 5*4.

You should be able now to compute the surface areas.

Step-by-step explanation:

4 0

3 years ago

A simple random sample of 100 observations was taken from a large population. The sample mean and the standard deviation were de

olga2289 [7]

Answer:

Se=1.2

Step-by-step explanation:

The standard error is the standard deviation of a sample population. "It measures the accuracy with which a sample represents a population".

The central limit theorem (CLT) states "that the distribution of sample means approximates a normal distribution, as the sample size becomes larger, assuming that all samples are identical in size, and regardless of the population distribution shape"

The sample mean is defined as:

$\bar X =\frac{\sum_{i=1}^n x_i}{n}$

And the distribution for the sample mean is given by:

$\bar X \sim N(\mu,\frac{\sigma}{\sqrt{n}})$

Let X denotes the random variable that measures the particular characteristic of interest. Let, X1, X2, …, Xn be the values of the random variable for the n units of the sample.

As the sample size is large,(>30) it can be assumed that the distribution is normal. The standard error of the sample mean X bar is given by:

$Se=\frac{\sigma}{\sqrt{n}}$

If we replace the values given we have:

$Se=\frac{12}{\sqrt{100}}=1.2$

So then the distribution for the sample mean $\bar X$ is:

$\bar X \sim N(\mu=80,Se=1.2)$

5 0

3 years ago